Through cooperative efforts with the MN DNR, the 14 Lake Minnetonka communities, and private citizens around the lake, the LMCD had been managing the growth of Eurasian Watermilfoil on Lake Minnetonka since 1989. Permits to harvest curly-leaf pondweed (CLP) were obtained since 2017 due to the increase in its presence. Tons of vegetation and biomass were removed from the lake over the years. View the harvesting reports for more details. In 2019, the Board suspended the harvesting program for three years to review vegetation management options and obtain public input. In 2021, the Board directed staff to sell the harvesting equipment.
Private residents around the lake made generous donations to support the initial purchase of harvesting equipment, which was replaced in the 2000s. The LMCD had operated three paddlewheel harvesters and a transport barge that was purchased in 2003. The three paddlewheel harvesters were purchased prior to the 2003, 2005, and 2012 seasons. Funding decreases in 2016 resulted in the reduced operation of two harvesters and a high speed transporter.
The harvesting season generally ran from mid-June through mid-August. The LMCD hired seasonal employees to perform the harvesting. The harvesters cut the EWM and CLP approximately three to six feet below the water surface and removed it from the lake onto the harvester. Vegetation removed from the lake was disposed of at various compost sites located in the area. Floating vegetation from fragments from boat traffic was also skimmed from the lake and at launches. In 2018, pilots were implemented to allow residents to dispose of their vegetation as part of the harvesting program where feasible and integrated a private-public partnership to allow coordination of vegetation disposal and transport. This program provided a supplemental and alternative to the use of chemicals for vegetation management.
Harvesting priorities were based upon impediment to boat navigation on the open water, with higher priority given to public navigation areas of the lake that were matted. The focus was to provide watercraft navigation from docks to open water.
LMCD used a combination of clear-cutting and channel-cutting to address harvesting priorities depending on the location and density of docks in the area. Sometimes tandem cutting was used or 180º skimming to minimize vegetation fragments. Other factors included weather and wind, and types of vegetation. Annually, areas that dictate the need for harvesting were cut once, with high growth areas harvested twice if time permitted.